TY - CONF A1 - Schühle, Florian A1 - Richter, Matthias T1 - Determination and classification of seven-day uptake rates for indoor air VOCs into tube type diffusive samplers with Tenax® TA N2 - Axial passive sampling of VOCs with Tenax® TA and thermal desorption GC-MS analysis is an accepted alternative to active sampling in occupational hygiene. In theory, the uptake into the passive sampler is only dependent on the diffusion coefficient of the analyte in air and the geometry of the sampler (ideal adsorption). For characterization, the uptake rate (UR) is used defined as the ratio of the mass adsorbed and the product of ambient concentration and exposure time. Various reported effective uptake rates (UR,eff) differ to an increasing degree from ideal values (UR,id) with increasing exposure doses (denominator of the given definition of UR), (Tolnai, 2001). In national and international standards, uptake rates are essentially sorted by the applicable exposure time, while detailed information about the corresponding concentration range is lacking. Moreover, especially for long exposure periods as applied in indoor air monitoring, the number of itemized substances is limited. Therefore it is the aim of this contribution to review and expand uptake rate data by comparison of literature and own laboratory values of assured quality. Passive samplers were exposed to nine single compound atmospheres of known concentrations for seven days. Concentrations were checked twice a day via active sampling.The determined uptake rates are considered accurate in terms of RSD and comparability to literature values and can be recommended for exposure times of seven days at 50 – 100 μg m-3 (approximately 100 – 300 ppm min). Seven-day uptake rates in ISO16017-2 and ASTM D6196 are not generally suited for this purpose, as has been exemplarily shown for benzene. Thus, it is crucial for optimization of the method to produce more reliable uptake rate data, including specific information about applicable exposure times and concentrations, which will be promoted in the course of this ongoing study. T2 - Healthy Buildings America 2021 CY - Online meeting DA - 18.01.2022 KW - Diffusive sampling KW - Volatile organic compounds (VOC) KW - Effective uptake rate PY - 2022 UR - https://www.isiaq.org/docs/HB2021America262.pdf AN - OPUS4-54372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -